Explosive



. UNITED STATES PATENT OFFICE.

DEMITRY MINDELEFF, OF SAN FRANCISCO, CALIFORNIA.

EXPLOSIVE.

SPECIFICATION forming part of Letters Patent No. 440,921, dated November18, 1890.

To all whom it may concern.-

Be it known that I, DEMITRY MINDELEEE, of San Francisco, in thecount-yof San Francisco and State of California, have invented certainnew and useful Improvements in Explosives; and I do hereby declare thatthe following is a full, clear, and exact description thereof.

This invention is an improvement in ex plosives, and its object is toprovide an explosive insensible to concussion that can be handled withmore safety and will yet have a greater explosive force than theordinary high-power explosives.

The improved explosive consists, essentially, of a combination ofnitrate of ethyl, nitrate of methyl, pyroxyline, and nitro-glycerine,and in combination of such elements with nitro-benzine, xyloidine, andpenta nitrocellulose, which substances are combined and preparedsubstantially in the proportions and manner hereinafter clearly setforth and claimed.

For the purpose of clearness and conciseness in the description, I willrefer to some of the sub-combinations of elements employed incompounding my explosives by letters, as occasion may arise hereinafter.

In order to produce the most perfect resul s, I prefer to produce ortreat some of the sub stances used in the explosive in a particularmanner to purify them and facilitate their intermingling and coalescencein the explosive, and shall herein specify which of the substances I soprepare and the manner of preparing them, but do not herein claim suchmethods.

With these observations I will proceed to describe the preparation ofthe explosive. One of the principal ingredients in my explosive isnitro-glycerine; but the common nitro-glycerine employed in themanufacture of dynamite and made by ordinary processes containsimpurities in considerable quantities and is objectionable or unfit formy purpose, and I therefore purify this common nitro-glycerine asfollows: Common nitro-glyc erine contains, as shown by analysis, one ormore or all of the following impurities: Sul phate of lead (plumbicsulphate Pb,SO,) and such as are produced by thechemical action of thenitric and sulphuric acids on theleaden Application filed August 19,1890- Serial No. 362/241. (No specimens.)

vessels generally employed in the manufacture of nitro-glycerine. Thelead salts are insoluble in water and are not separated from the commonnitro glycerine during the process of washing, but remain mechanicallysuspended therein. Another impurity is protosulphate of iron (Fe,SO,,Aq)resulting from the action of acids on the iron vessels employed inmaking thecommon nitro-glycerine. WVhile such salt is soluble in water,yet it is oxidized thereby during the process of washing commonnitroglycerine, and deposits a portion of oxide of iron, (Fe ,O whichremains mechanically suspended in the common nitroglycerine. Again, thecommon nitro-glycerine generally contains fatty acids derived from thecrude glycerine, such as stearic, margaric, oleic acids, &c., and moreor less water. The presence of these impurities in commonnitro-glycerine is evidenced by its impure cloudy color, as whenthoroughly purified it is transparent. To get rid of these variousimpurities in the nitro-glycerine to be used in compounding myexplosive, I take about seventy-five, eighty, or even eighty-five partsof common nitro-glycerine and add thereto sufficent ethyl alcohol tomake one hundred parts in volume of the mixture. The stronger and purerthe alcohol the less it is necessary to add, or a larger percentage ofnitro-glycerine can be used. This mixture is gently agitated until theingredients are thoroughly commingled, and is then left to settle. Intwo or three hours the mixture will separate into two distinct layers,each transparent and of a light yellow color. The upper layer of themixture will be the ethyl alcohol, and contains in solution fatty acidsand water derived from the common nitro glycerine, and perhaps a smallquantity of such nitroglycerine. This upper layer should be removed bysiphonage or decantation, as the ethyl alco* hol does not enter into thecomposition of my explosive, and is used merely as a means of purifyingthe common nitro glycerine, and must be entirely removed, since itspresence will interfere with the union of the purified nitro-glycerineand other ingredients. The lower layer of such mixture consists ofnitroglycerine containing a small quantity of sulphate of lead and oxideof iron; but these impurities will gradually precipitate themselves tothe bottom, or could be separated from the nitro-glycerine byfiltration. This leaves the nitro-glycerine pure and colorless, and Iwill distinguish it from common nitroglycerine hereinafter by naming itpurified nitro-glycerine. Again, I take one part of ni-' trate of ethyl(nitroethyl O H ,NO and one part of nitrate of methyl (nitro-methylen OH,NO and mix these together and dissolve therein about ten per cent. ofpyroxyline. All threejof these substances are highly explosive, bothseparately and incombination. This combination of ingredients I willrefer to hereinafter as mixture B. Again, I take one part ofnitro-benzine (C H ,NO or dinitro-benz'ine (O H NO and mix with it anequal volume of methyl alcohol, and dissolve in this mixture pyroxylineup to the point of saturation. This mixture of ingredients I willhereinafter call mixture 0.

The combination of purified nitro gly'c'erine and mixture B produces'apowerful explosive,

the proportions being about thirty-five parts of purifiednitro-glycerine to fifteen parts of mixtureB. Again,combiningthirty-fi-ve parts of purified nitro-glyc'erine' with fifteenparts of mixture 0 will aifor'd a powerful non-sensitive explosive; butto make the most powerful explosive I take about seventy parts ofpurified nitro-glycerine, fifteen parts of mixture B, and about fifteenparts of mixture 0 and thoroughly incorporate the same. This finalproduct constitutes a most powerful explosive, and is the base and bodyof my improved explosive compound, and it has a semi-fluid consistency.I may add to this compound powdered pyroxyline, commonly known aspressed pyroxyline or xy'oloidine, (as ordinarily prepared.) Either ofthese will thicken this compound and make it plastic, and I use eitheras may be found most convenient and economical, according zine, methylalcohol, pyroxyline, and nitroto the location of the factory and thepurpose for which the explosive is to be employed. The addition ofnitro-benzine, methyl alcohol, and pyroxyline (mixture 0) is valuable inproducing my explosive, as they render it non-sensitive to concussion.

dangerous to incorporate pyroxyline with ordinary nitro-glycerine; butthe purified nitroglycerine and compounds above described It isextremely will readily and safely dissolve aconsiderable quantity of thesoluble pyroxyline.

To increase the explosive force of my compound, I use, instead ofpressed pyroxyline or xyloidine, an expressly-prepared form ofpyroxyline, which is produced as follows: Itake strong nitric acid, heatit to boiling, and add thereto as much soluble pyroxyline as the acidwill dissolve. I subsequently pour this solution into five or sixvolumes of cold water. The pyroxyline is separated from the acid and isprecipitated in a finely-divided powder, whichissubsequentlythoroughlywashedfrom the acid and dried. This precipitatedpyroxyline Icall penta nitro-cellulose, and add as much of it to thecompound as is necessary to make it plastic. The compound described istransparent and might adhere to the exterior of vessels without beingnoticed.

To prevent accidents, I preferably stain it with aniline, cochineal, orother pigment that would not affect the compound or any of itsconstituents.

This improved explosive will not explode on concussion. Ignited in theopen airit will burn slowly until it reaches a temperature of about 280centigr'ade, when it explodes; 'It can be loaded into shells forartillery and safely fired from a cannon, and is also useful fortorpedoes and other appliances of war, and is practically a safeexplosive for industrial purposes. 7

To explode the compound, I use a detonator of fulminate.

Having described my invention, what I claim as new, and desire to secureby Letters Patent thereon, is-- 1. An explosive compound consisting ofnitrate of ethyl, nitrate of methyl, pyr'oxyline, nitro-glycerine, and anon-sensitizing mixture, substantially as described.

2. An explosive compound consisting of nitrate of ethyl, nitrate ofmethyl, nitro-benglycerine, substantially as described.

In testimony that I claim the foregoing as my own I aflix my signaturein presenceof two witnesses. 7

DEMITRY MINDELEFE Witnesses:

ARTHUR E. DOWELL, PERCY L. BROOKS.

